GB1446554A - Friction discs - Google Patents

Abstract

1446554 Multi-plate brake friction discs; friction clutches DUNLOP Ltd 4 Dec 1973 [20 Dec 1972] 58890/72 Headings F2E and F2C A carbon friction disc for a brake or clutch comprises an annular carbon member 1, Fig. 1, one periphery of which is provided with a number of discrete, circumferentially-distributed carbon torque-transmitting inserts 4 reinforced by filamentary material, the inserts being at least partially formed by a separate sequence of operations from those used to form the annular member 1. In a brake, the discs may be stator discs keyed at their inner peripheries to a torque tube or rotor discs keyed at their outer peripheries to a wheel. In the disc of Fig. 1, specifically for a multidisc aircraft brake, the insert 4 incorporating a keyway 2 is formed from a matrix of carbon and carbonised laminations of cloth, or carbonised felt, and bonded into a cut-out 5 provided in the outer periphery of the annular member 1 formed from a matrix of carbon and a carbonised circumferential winding of tape. In Fig. 3, (not shown), such an insert is thinner and inserted in a groove in the edge of the member so that only the peripheral face and keyway are visible. Fig. 5 shows a key 17 with a surrounding tongue 15 in a groove 16 strengthened by pins 19 reinforced by filamentary carbon. Torque is transmitted at 18. In Fig. 4 (not shown) the tongue and pins are omitted from such a key. In Fig. 2 (not shown), such a tongue and pins are added to the insert 4 of Fig. 1. In Fig. 6 (not shown) a key has a narrower surrounding tongue with serrations on the tongue surfaces cooperating with serrations in the groove. In Fig. 7 (not shown) a key without a tongue has a dovetail base located in a cut-out in the annular member, and the portion of the key projecting beyond the disc has shoulders which abut the outer periphery of the annular member. In Fig. 10 a laminated cloth insert 31 has the edges of the keyway reinforced by layers of tape 32 and the contacting edges of insert and annular member are reinforced by layers of tape 33, 34, respectively. Fig. 9 (not shown) resembles Fig. 10 but the keyway reinforcement is extended over the outer periphery of the insert, while the "contacting" reinforcements are omitted. Fig. 8 (not shown) depicts a U-shaped insert made wholly of layers of carbonised tape each in the form of a U. In Fig. 11 (not shown) inserts resembling those of Fig. 1 are inserted as an uninterrupted array in cut-outs in the inner periphery of an annular stator member. Inserts 35, Fig. 13, for stator discs have a key 36 and tongues 37, the tongues abutting when installed. In Fig. 14 carbonised-tape-layer inserts 40 have the bases of the keyways defined by carbonised-cloth reinforced fillets 41. In Fig. 16 a rotor key 42 reinforced with carbonised filamentary material engages recesses 44 (which are optional) in an annular member 43 of random-fibre-reinforced carbon. In Fig. 17 keyways 46 are strengthened by carbonisedcloth-reinforced carbon blocks 47 partially recessed into the annular member